1. Field of the Invention
The present invention relates to a cationic electrodeposition coating composition and a method of preparing the cationic electrodeposition coating composition, and more particularly to a cationic electrodeposition coating composition coated on a base frame to form a film having improved characteristics, and a method of preparing the cationic electrodeposition coating composition.
2. Description of the Related Arts
A hard disc driver as one of secondary memory units of a computer writes data in a magnetic disc by a magnetic head or reads data stored in the magnetic disc. A base frame manufactured by a die-casting of an aluminum alloy is required to protect the hard disc driver. In order to protect the base frame, a continuous coating film is formed on the base frame by an electrodeposition coating method. Lead-free cationic epoxy electrodeposition paint had been applied to coat the base frame of the hard disc driver. In general, tin acts as a catalyst for promoting a curing reaction of the cationic epoxy electrodeposition paint. An electrodeposited film of paint coated by a tin-free cationic electrodepositing paint is cured at a high temperature of at least about 180° C. The base frame would be thermally deformed when being cured at the high temperature. The electrodeposited film of paint is dried at high temperature so that energy for forming the film is greatly increased. Also, a pinhole may be generated when the base frame of the hard disc diver is electrodeposition coated by the tin-free cationic epoxy electrodeposition paint. Therefore, the appearance of the base frame may be deteriorated, and the aluminum alloy may be exposed so the operation performance of the hard disc driver may be affected.
Also, the conventional cationic epoxy electrodeposition paint includes lead to improve corrosion-resistance of the film formed by the electrodeposition paint, and as a result, environment is polluted. Presently, the environmental pollutants such as lead and tin are restricted in use.